This project involves cultivation of cells derived from normal and abnormal female lower genital tract epithelia. The cells are serially passaged with support from feeder layers of lethally irradiated mouse 3T3 cells (the Rheinwald-Green system). The overall objectives for this culture system are two-fold: to study the growth and differentiation of the epithelial cells and to investigate the etiology and progression of cervical carcinoma. So far, our results on optimizing the growth of normal cells by varying concentration of factors such as hydrocortisone, cholera toxin, epidermal growth factor as well as feeder layer density and cell type are consistent with a recent report that the cells grow well (Stanley and Parkinson (1979) Int. J. Cancer 24:407). Human cervical cells at varying stages of dysplasia or carcinoma will be propagated and examined for dependence upon growth factors and feeder support and for expression of differentiated character (keratins, cross-linked envelopes, cytochrome P450, estrogen receptors). In addition to permitting characterization of the cellular differentiation and possibly mechanisms of tumor progression, the results of this work may also indicate to what extent keratinocytes from different anatomical locations (epidermis, cervix) differ in culture.